Уточнить поиск
Результаты 391-400 из 575
Denaturing Gradient Gel Electrophoresis (DGGE) Analysis Indicating Increased Microbial Diversity in Landfill Area Near Conserved Wetland Полный текст
2023
M. B. Chakraborty, S. R. Patgiri, A. S. Rahman, A. Dasgupta and G. Pegu
The ecological balance of an ecosystem has a relation to its biodiversity. Although it has been established that biodiversity and ecological stability are related, generalization about the exact nature of this relation remains elusive and more so in microbial diversity. A growing volume of studies has indicated that anthropogenic activities impact biodiversity, but it is difficult to generalize the impact of anthropogenic activities on microbial diversity. Landfilling by municipal solid waste is one such activity where microbes play a major role, and leachates are released from the landfill, altering the soil’s physical and chemical nature. Change in factors like carbon source, pH, and toxicity of the soil is most likely to affect the indigenous microflora of the soil. The present study was undertaken to compare the microbial diversity of soil receiving landfill leachate with that of the soil not receiving any landfill leachate to assess the impact of the landfilling activity on microbial diversity. The landfill site selected for the study was that of Kamrup Metro District of Assam, located at Boragaon, near the Ramsar wetland called Deeporbeel. By using the Denaturing Gradient Gel Electrophoresis (DGGE) method, it has been found that the microbial diversity of the soil receiving leachate was higher than that of the soil not receiving any leachate from the landfill.
Показать больше [+] Меньше [-]Effect of Compliance with Environmental Regulations in the Construction of Public Civil Works, Cajamarca, Peru Полный текст
2023
D. Quinto, D. Sanchez, M. Milla, M. Torres, B. Cayatopa, D. Jara and E. Morales
Construction activities produce considerable environmental effects and have resulted in a growing demand to implement favorable environmental practices. In this sense, this research aimed to evaluate the effect of the level of compliance with environmental regulations in public civil works in the San Ignacio, Cajamarca, Peru district. Data were obtained through direct observation and structured interviews in 7 selected construction sites. The deductive and analytical method was used. As a result, the level of compliance was obtained. Work 4 had the highest rank, and works 2 and 5 had the lowest. Currently, all the works are in a similar range of compliance. The degree of association between the level of compliance with environmental regulations and the current state of the civil works indicates a probability of 0.0190, which shows that the low level of compliance with environmental regulations in the construction of public civil works in the district of San Ignacio generates a deterioration in the quality of the environment and increases the possibility of administrative sanctions.
Показать больше [+] Меньше [-]Stabilisation of Spent Wash by Polyhydroxybutyrate (PHB) Producing Microorganisms Isolated from Karad Region, Maharashtra Полный текст
2023
G. V. Patil and G. R. Pathade
In recent years, there has been a significant increase in the needs of the overgrowing population. Naturally, industrial belts increased worldwide to satisfy the variety and quantity of needs. While producing the products, a huge quantity of waste is generated and added continuously to the environment, causing hazardous effects on the flora and fauna. Spent wash is one of the most important types of industrial waste since it is the liquid waste that is left over after making alcohol and it pollutes the environment. Despite effluent quality standards, untreated or partially treated sewage frequently enters water courses or soils. It is always overloaded with organic and inorganic substances. The stabilization of the effluent by microorganisms is reflected in the form of COD reduction. The present study attempted to isolate the PHB-producing organisms and use them to stabilize the spent wash. The locally isolated, characterized, and identified 11 PHB-producing microorganisms from the Karad region of Maharashtra were used to stabilize spent wash. They include Candida orthopsilosis, Bacillus subtilis, Bacillus cereus, Bacillus megaterium, Klebsiella grimontii, Citrobacter fruendii, and members of Staphylococcus and Rhodococcus. All potential organisms were reported to stabilize the spent wash. The degree of stabilization was measured in terms of the percent reduction of COD and BOD. The % reduction was reported at 95.31% and 81.39% of COD and BOD, respectively, by Klebsiella grimontii, followed by 92.18% and 80.46% reductions of COD and BOD, respectively, by Staphylococcus. These organisms are promising in the treatment of spent wash.
Показать больше [+] Меньше [-]Tests for Evaluating the Efficacy of Phosphoric Acid Activated Charcoals from Two Biomasses Полный текст
2023
Abhijit S. Jadhav and Ravindra Nalawade
Good quality activated charcoals were prepared from areca nutshell and coconut shell using phosphoric acid as a chemical activating agent at 400oC. Physico-chemical properties like iodine number, methylene blue number, and surface area of two activated charcoals were measured to assess the porous nature. A special test called acetic acid number was devised to understand the quality of functional groups on charcoal surfaces. Proximate analysis and physical properties of the two activated charcoals closely matched those of a commercial sample, confirming the good quality of samples prepared in the laboratory. Adsorption of isolated caramel from waste stream obeyed Freundlich isotherm, and the data could be explained based on the physisorption of large size molecules on the walls of mesoporous solid surface. Adsorption of methylene blue involving Coulombic attraction towards the areca nut shell-derived activated charcoal could be predicted and confirmed based on the acetic acid number for the first time.
Показать больше [+] Меньше [-]Effects of Corn Straw Biochar, Soil Bulk Density and Soil Water Content on Thermal Properties of a Light Sierozem Soil Полный текст
2023
Y. Q. Li, L. J. Li, B. W. Zhao, Y. Zhao, X. Zhang and X. Dong
This research aimed to quantify the effects of biochar derived from corn straw on soil thermal conductivity, capacity, and diffusivity. Firstly, the amount of biochar application (w/w) added to light sierozem soil was 0% to 5%, and the mixtures were packed into soil columns at a consistent bulk density (1.20 g.cm-3). Secondly, soil columns with a consistent biochar addition rate (5%) were packed to different bulk densities of 1.30, 1.25, 1.20, 1.15, and 1.10 g.cm-3. Soil thermal characteristics were measured under the control of soil moisture content from 0% to 40%. Under consistent bulk-density conditions, biochar could significantly reduce soil thermal conductivity and diffusivity. Still, there wasn’t a significant influence on soil heat capacity in most soil moisture content levels. With the decrease of soil bulk density, soil thermal conductivity, capacity, and diffusion coefficient reduced significantly. As soil water content increased, all the indexes of thermal properties largely improved, and the effects were much more significant than those of biochar amendment and bulk density change on soil thermal performances. This research could supply an implication to evaluate the influence of biochar amendment on soil thermal performances.
Показать больше [+] Меньше [-]Comparative Study on the Indoor Air Quality in Critical Areas of Hospitals in Malaysia Полный текст
2023
Kerk Teck Seng, Lee Chia Shen, Ngo Sin Ling, Sim Pei Chin, Tan Jia Xin, Tan Kai En, Adnaan Ahmed Jama, Azian Hariri and Nurul Fitriah Nasir
Indoor Air Quality (IAQ) is the air quality within and around buildings and structures, particularly regarding building occupants’ health and comfort. IAQ assessments were performed using an objective measurement of molecular gaseous pollutants to determine the IAQ profile in the hospital’s critical areas. It also analyses the effects on patients in different environments and the sources that result in deviations from approved criteria. This comparative study is aimed to investigate the concentration of different compounds in different critical departments in the hospital and propose solutions to the related problem as an improvement in indoor air quality. The data was compared with the standards and regulations. It was found that the TVOC level in the CCU department, specifically in the fluoroscopy room, has exceeded the allowable limit. A few suggestions have been raised to lower the exceeded value. The risks and symptoms held by the occupants in the hospital buildings if they face poor indoor air quality were discussed. Further study can be conducted to relate the short and long-term health issues among medical staff to poor indoor air quality.
Показать больше [+] Меньше [-]A Review of Research on Materials for the Separation of Oil/water Mixtures Полный текст
2023
Xu Meng , Chengzhi Song, Junfeng Yan, Yanyan Dong, Aiqin Hou, Kongliang Xie and Liping Liang
Water pollution caused by oil spills at sea and industrial and daily wastewater discharges are causing serious damage to the ecological environment, not only in terms of economic losses but also in terms of human health and survival, a problem that needs to be addressed urgently. Oil/water separation is a global challenge, and while these problems are frequent, various oil/water separation strategies have been extensively investigated in recent years. The efficiency of the materials prepared is a key factor, as are the environmental friendliness and low cost of the methods and raw materials used in the experiments. This work reviews methods and materials applied in oil/water separation in recent years, including natural textile materials, metal meshes, synthetic membranes, particulate adsorbent materials, foams, sponges, aerogels, smart controllable special wettable separation materials.
Показать больше [+] Меньше [-]Efficacy of Nanofertilizers Over Chemical Fertilizers in Boosting Agronomic Production Полный текст
2023
A. Khatri and R. Bhateria
Global agricultural production cannot catch the increasing population’s exigency. At different times, the world has faced food crises of varying intensity. Many steps have been taken after that to encounter the rising concerns. Nowadays, nanofertilizers are being experimented with as an alternative to conventional fertilizers. Nanofertilizers can be classified as macronutrients and micronutrients nanofertilizers. Synthesis of macronutrient nanofertilizers (nitrogen, phosphorus, potassium, calcium, magnesium, etc.) and micronutrient nanofertilizers (iron, boron, zinc, copper, silicon, etc.) can be done using chemical and green synthesis methods, which involves reducing agents, capping agents, dendrimers, microbial synthesis, solvents, and others. Composition of the nanofertilizers can be done using top-down and bottom-up approaches incorporating hydrocarbon polymer, dendrimers, microbes, etc., which decides their usage in various crops depending upon the requirement of the plant. Engineered nanofertilizers can improve crop yield by mitigating environmental pollution, environmental stress, and plant diseases. However, the unsystematic use of nanofertilizers can be a hurdle in its utilization. This article discusses various types of nanofertilizers with their unique properties and applications. Each category of nanofertilizers is explained considering their composition, particle size, concentrations applied, benefited plant species, and plant-growth enhancement aspects.
Показать больше [+] Меньше [-]The Impact of High-Concentration Salt Solution on Morphological Changes in a Geosynthetic Clay Liner Полный текст
2023
N. P. Nisha and J. Prakash Arul Jose
Microscopic examination was used to begin investigating the changes in geosynthetic clay liner (GCL) specimens that had been hydrated with two separate solutions: pure water and a 50 percent concentration NaCl solution. After already being hydrated with NaCl aqueous solution, the GCL samples were examined under an electron microscope. Even though the treated GCL samples’ surfaces mirrored those of the untreated GCL, a crystal deposit was found there. It was found that the bentonite particles in the GCL sample appeared more solid after being hydrated with distilled water as opposed to the NaCl solution using a scanning electron microscope (SEM). It seems that wetting the salt solution decreases the bentonite particles’ tendency to swell. Additionally, it was demonstrated by the energy-dispersive X-ray spectrometer (EDS) data that distilled water hydration had no impact on the distribution of the elements identified in the GCL samples. On the other hand, the presence of bound chlorine demonstrated that the bentonite particles had absorbed the NaCl solution. The hydrated GCL sample’s hydraulic conductivity showed some variation as well.
Показать больше [+] Меньше [-]Analyses of Polycyclic Aromatic Hydrocarbons (PAHs) in the Ganga River Water in Uttar Pradesh, India Полный текст
2023
Poonam Sonwani and Sandhya Bharti
Polycyclic aromatic hydrocarbons (PAHs) were analyzed in the Ganga River water samples collected from three cities. Jajmau (Kanpur), Dala Khera (Fatehpur), and Kara Kachar (Kaushambi) of Uttar Pradesh, India. At Jajmau (Kanpur), out of sixteen PAHs, eight were found in the Ganga river water in concentration (μg.L-1) order: acenaphthylene (3.8356) > pyrene (0.5878) > fluorene (0.5752) > anthracene (0.2806) > benzo(b)fluoranthene (0.1960) > phenanthrene (0.0526) > benzo(a)pyrene (0.0234) > naphthalene (0.006). In contrast, in Dala Khera (Fatehpur), two PAHs: anthracene (0.2806) and fluorene (0.07894), were observed. In Kara Kachar (Kaushambi), only single phenanthrene (0.04507) was detected. It was noticed that the three-ring types of PAHs occur commonly in all three sites. It is concerning because the river water sampled had PAH concentrations, namely Acy, Flu, Phe, and Pyr, that were relatively higher than those recommended (0.05 μg.L-1) by WHO (1998) in surface water. In contrast, the amounts of Nap, Ant, BbF, and Bap were recorded within the safe levels in Kanpur, while in the other two cities (Fatehpur and Kaushambi), Phe and Ant were detected lower than their permissible limit. Flu was measured as higher than its recommended value by WHO (1998). Similarly, the concentration of Acy, Ant, Pyr, BbF and BaP in river water samples at Jajmau, Kanpur were higher than their safe limits suggested by RIVM report 607711007/2012 for inland surface water while Nap, Flu, and Phe were lower than their recommended values. However, at, Dala Khera and Kara Kachar (Fatehpur and Kaushambi respectively), the concentrations of Ant, Flu and Phe were lower than their prescribed limits given by RIVM 607711007/2012.
Показать больше [+] Меньше [-]